1. Field of the Invention
This invention relates generally to a system to anchor a catheter or medical article in position upon a patient. More specifically, this invention relates to an anchoring system which retains a medical article in position upon a patient without crimping, kinking, or occluding the lumen of the medical article and which permits easy repositioning of a length of the medical article within the anchoring system.
2. Description of the Related Art
It is common in the treatment of patients to utilize catheters to introduce fluids and medications directly into the patient or to withdraw fluids from the patient. An example of a typical catheter is a percutaneous drainage tube, which is used to drain fluid from an abscess within the body. In placing a percutaneous drainage tube, it is preferable to fix the distal end of the percutaneous drainage tube as deep as possible within the abscess. As the abscess drains and closes, the percutaneous drainage tube may need to be withdrawn progressively.
During this process, the catheter may remain in place for many days. In order to secure the catheter in position at the insertion site, a healthcare worker often secures the catheter to the patient using tape. That is, the healthcare worker commonly places long pieces of tape across the portion of the catheter near the insertion site in a crisscross pattern to secure the catheter to the patient""s skin. This securement inhibits unintentional migration of the distal end of the percutaneous drainage tube.
However, normal protocol requires periodic (e.g., daily) tape changes. Tape changes are also necessary if it becomes necessary to adjust the placement of the distal end of the percutaneous drainage tube as discussed above. These tape changes are time consuming, and repeated placement and removal of tape can excoriate the skin of the patient in the taped region. Because many healthcare workers find the taping procedure cumbersome and difficult to accomplish when wearing gloves, they often remove their gloves when taping. Not only does this increase the amount of time spent on the taping procedure, but it also subjects the healthcare worker to an increased risk of infection.
A variety of catheter securement devices have been developed to obviate the need for frequent application of tape to secure a catheter to a patient. One such securement device provides a flexible clamp with winged extensions that are sutured to the patient""s skin. In some applications, the winged extensions are integrally formed with catheter. In other applications, the flexible clamp is covered by a rigid fitting, which receives the catheter/clamp combination in a friction-fit manner. The rigid fitting and flexible clamp are formed with lateral, aligned holes, which allow the combination to be sutured to the patient""s skin. Although these suturing devices securely attach the catheter to the patient, it is obviously painful and uncomfortable for the patient. These devices are also time consuming and inconvenient to secure, pose the risk of needle-stick to the healthcare worker, and risk suture-site infection to the patient.
In addition, suture material tends to exhibit poor gripping on medical tubes and can cut through the winged extension of the flexible clamp if a rigid clamp is not used. However, the use of a rigid fitting complicates the securement procedure by adding yet another component that can be dropped on the floor and become unsterile. In addition, the sutured securement of the flexible clamp and/or the rigid fitting assembly does not permit easy release of the catheter from the patient for dressing changes and insertion site cleaning. A removal instrument (e.g., sterile scissors) also is generally required for suture removal.
One device which attempts to address these concerns is disclosed in U.S. Pat. No. 5,685,859. This device uses an adhesive pad that is attached to the skin of the patient and that surrounds the insertion site of the percutaneous drainage tube. The tube is bent over a plaster surface to lie flush with the pad and an adhesive flap is secured over the percutaneous drainage tube, holding it in place. However, it is difficult to reposition the percutaneous drainage tube when using this device. The healthcare worker must remove the adhesive flap without removing the adhesive pad, which results in poor adhesion if the same device is resealed over the tube at its new position. If a new device must be placed, then the old one must first be removed, which is even more time consuming than removing and replacing tape, and also results in excoriation of the skin.
To overcome these difficulties, the present invention involves the recognition that it would be desirable to create a securement device which releasably held a percutaneous drainage tube or other medical article in a fixed position, but which allowed for axial adjustment of the position of the medical article relative to the patient, as well as allowing the same securement device to be used over the duration of the use of a percutaneous drainage tube. The system preferably is operable without removing surgical gloves and adjustments in position can be made without the need to completely redress the insertion site.
The present anchoring system secures an medical article in a fixed position, yet permits easy repositioning of the medical article within the anchoring system, as well as easy release of the medical article from the anchoring system for dressing changes and other medical procedures. Unlike prior anchoring systems, the current anchoring system also preferably is not limited to a single medical article size. In this way the present anchoring system can be used with various medical articles having a range of sizes.
One aspect of the present invention involves an anchoring system for a medical article. The anchoring system comprises a retainer including a base and a compressible member. The base has a cavity and the compressible member is disposed within the cavity. The compressible member defines a receptacle that is configured to receive at least a portion of the medical article. At least a deformable portion of the compressible member is deformable in a manner that produces internal compressive stresses within the compressible member. These internal stresses contribute to increased normal forces that bear against the portion of the medical article that is received within the receptacle. As a result, the frictional force between the compressible member and the receive portion of the medical article is increased.
In a preferred mode, the receptacle is a channel that has a curvilinear shape. This shape furthers the frictional force acting upon the medical article when an axial force is applied to the medical article to draw it through the channel. As a result, axial movement of the medical article through the channel is further inhibited.
The anchoring system may also include at least one biasing member. The biasing member is inserted into an aperture within the compressible member and in doing so deforms at least the deformable portion of the compressible member. In this manner, the compressive force within the compressible member, which acts upon the received portion of the medical article, is produced.
The anchoring system can also be part of a catheterization system that also includes one or more medical articles. In one mode, the medical article is selected from a group consisting of catheters and tubes, and the compressible member is formed of a material that is softer than a material from which the catheter or tube is formed. For example, the compressible member can be made of a thermal plastic elastomer that has a Shore A hardness of less than 50 durometer.
The anchoring system may also include an anchor pad. The anchor pad has a first surface including an adhesive layer to adhere the pad to the patient""s skin, and an opposing second surface to which the retainer is attached.
In accordance with another aspect of the present invention, an anchoring system for securing an elongated medical article to a patient is provided. The anchoring system includes an anchor pad and a retainer. The anchor pad has a first surface including an adhesive layer to adhere the anchor pad to the patient""s skin, and an opposing second surface to which the retainer is attached. The retainer includes a base and a cover that is pivotally attached to the base and is movable between an open position and a closed position. A receptacle is defined between the base and the cover to receive a portion of the medical article. The receptacle has first and second longitudinal ends and is configured to engage the received portion of the medical article so as to inhibit longitudinal movement of the medical article through the receptacle. A guide extension is disposed next to one of the first and second longitudinal ends of the receptacle. The guide extension has a curvilinear surface over which the elongated medical article can track so as to smoothly transition an axial orientation of a portion of the medical article, which is adjacent to the received portion of the medical article, along the length of the adjacent portion.
In one mode, the guide extension has an arcuate shape having about a 45xc2x0 arc angle. This configuration allows the guide extension to support the adjacent section of the medical article through a similar degree turn. In this manner, the medical article can extend over the patient""s skin and then extend into the patient""s skin in a direction that is generally skewed relative to the skin. The guide extension, however, can extend through other arc angles (e.g., 90xc2x0 ) so as to vary the incident angle between the medical article and the patient""s skin.
The anchoring system, as noted above, can also be part of a catheterization system that also includes one or more of the medical articles. In one mode, the medical article(s) is a catheter and/or tube.
In one preferred variation of the present anchoring system, the system includes a flexible anchor pad to be attached to the skin of the patient, and a retainer which is mounted on the anchor pad. The retainer includes a base which has a cavity within which a compressible member is located. The compressible member includes a receptacle for receiving a portion of the medical article. In one preferred embodiment, the receptacle comprises a channel through the compressible member, which acts a channel support. A cover is attached to the base by a hinge mechanism which allows the cover to be opened to allow the insertion of the medical article into the channel, or closed to prevent inadvertent motion of the medical article within the channel. The cover is held in the closed position by a latching mechanism operating between the base and the cover. At least one guide extension provides a support surface for the medical article from the end of the channel to a surface of the anchor pad to inhibit kinking of the medical article as it exits the channel of the retainer and passes through the skin of the patient.
In a further preferred variation, the anchor pad is formed into a butterfly shape which provides additional lateral and longitudinal support to the retainer and medical article by extending the anchor pad beyond the insertion site of the medical article longitudinally.
In a preferred mode of manufacture, the entire retainer is integrally formed by a two-stage, over-molding injection process, such that the base, cover, latching mechanism, and hinge mechanism are formed in the first stage from a first material, and the channel support is formed in the second stage from a second material. The first material should be elastic enough to allow the latching and hinge mechanisms to be formed from it, but rigid enough to allow the base and cover to retain their shape. The second material should be softer and compressible to allow it to deform when a medical article is pressed against it, and have a high traction surface which inhibits inadvertent longitudinal motion of the medical article within the channel. In a further mode, an inner portion of the guide extension is formed of the first material in the first stage and an outer portion of the guide extension is formed of the second material in the second stage.
In accordance with the preferred method of anchoring a medical article onto a patient, which permits an axial position of the medical article to be repositioned relative to the patient, involves inserting a section of the medical article into a channel receptacle of a compressible member of an anchoring system. A compressive force is produced within the compressible member so as to increase the normal force acting upon the inserted section of the medical article, and thereby to increase the frictional force between the inserted section of the medical article and the compressible member. A cover is positioned over at least a portion of the channel receptacle and is secured at a position overlying the portion of the channel receptacle. In this manner, the cover and the compressible member inhibit transverse movement of the medical article, and the compressible member inhibits lateral and longitudinal movement of the medical article relative to the patient.
In a preferred mode, the method also involves releasing the cover and moving the cover away from the receptacle. The medical article is then pulled through the channel receptacle so as to axially reposition at least a portion of the medical article relative to the patient. The cover is repositioned over at least a portion of the channel receptacle and is secured in this overlying position.
In accordance with another mode, a section of the medical article, which is adjacent to the inserted section of the medical article, is tracked over a curve surface to inhibit kinking of the medical article as it exits the channel receptacle and extends to the insertion site.
Further aspects, features and advantages of the present invention will become apparent from the detailed description of the preferred embodiment that follows.